The invention has wide applications; however, as will become apparent, a preferred embodiment of the invention is particularly suitable for applications in electrostatographic reproducing machines. In a typical electrostatographic reproducing machine, a photoconductive insulating surface, often in the form of a moving belt, is uniformly charged and exposed to a light image from an original document. The light image causes the exposed or background areas to become discharged, and creates an electrostatic latent image on the surface corresponding to the image contained within the original document. Alternatively, a light beam such as a laser beam may be modulated and used to selectively discharge portions of the photoconductive surface to record the desired information thereon. The electrostatic latent image is made visible by developing the image with a developer powder, referred to in the art as toner, which may be subsequently transferred to a support surface such as paper to which it may be permanently affixed by the application of heat and/or pressure.
In order to minimize maintenance costs by permitting the operator to replace worn out or exhausted processing units in electrostatographic apparatus, it has been suggested to incorporate one or more processing units of the apparatus in disposable or removable cartridges or units. In this way the operator can readily remove each cartridge when its operational life has been exhausted and insert a new cartridge. In addition, it also provides the advantage of enabling less expensive functional features, such as the photoreceptor drum in a conventional copier. Typically, these processing cartridges include an imaging member such as a rotatable drum or an endless belt together with one or more of a charge corotron, a developing device and cleaning device.
In these applications, it is generally necessary to distribute power, high voltage and/or logic signals between the main frame of the machine and the removable processing unit or cartridge. Traditionally, this has taken the form of utilizing conventional wires and wiring harnesses in each machine to distribute power and logic signals between the main frame of the machine and the removable processing unit. For example, conventional plug and socket arrangements have been used which can be either manually connected or joined automatically on insertion of the unit into the main frame. This automatic joining requires precision positioning and alignment of the unit on insertion with very low tolerance for misalignment error. Typically, locating members such as pins or rails are used to insure proper positioning, all of which can negatively impact upon not only a large number of parts required to build the machine, but also upon the overall manufacturing cost. In addition, conventional wires and wiring harnesses are flexible and therefore, do not lend themselves to automated assembly such as with the use of robots leading further to increased manufacturing costs.
Presently, high voltage connectors are routinely manufactured by insert molding a preformed metal pin or socket into an insulating plastic housing. Often a suitable wire is simultaneously insert molded within the same connector housing to produce a complete connector assembly. There are, however, at least three to five separate steps to the present manufacturing process of conventional high voltage connectors.
While certain other electrical contacts have been proposed, they suffer certain deficiencies. For example, the use of two conventional metal plate contacts such as two spring biased metal tabs one on each of the main frame and the removable unit in addition to requiring the precision positioning and alignment discussed above can be rendered unreliable after only a short period of use in the hostile machine environment by having the contacting surfaces contaminated by dirt, toner, paper fibers, or other debris. Furthermore, such metal contacts tend to oxidize thereby forming an insulating layer on the contact surface and degrading further the reliability and performance of the contact.